doesn't go in on crutches or something like that. >> reporter: the sport is so popular, it even has a junior league. >> the future of women's flat track roller derby, little girls, getting out there, hitting hard action on the track. >> reporter: the derby bratz. girls as young as 8 with nicknames like hannah mon-slammah and primama basheri. another generation, derbies fans hope, will ensure this sport doesn't disappear again. >> if your daughter wants to play roller derby, you should be like, yes, that is strong women working hard. awesome. >> reporter: i'm ryan owens for "nightline" in austin, texas. hey, check it out. she's using the mr. clean magic eraser bath scrubber. i've heard of it, but i haven't seen one up close. what's the word around the sink? that it removes 3 times more soap scum per swipe, and it came from outer space. it is not from outer space! no, man, it's from outer space. they're aliens on an intergalactic cleanliness mission. they're here to clean up the universe. oh, the kitchen scrubbers are aliens, too?